Signaling and protocol for communication system with wireless trunk

• US 6,208,627 B1
• Filed: 12/10/1997
• Issued: 03/27/2001
• Est. Priority Date: 12/10/1997
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Xircom Incorporated (Intel Corporation)
• Inventors: Roeder, Konrad G. R., Menon, Narayan P.
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US08/988,546
• Time in Patent Office: 1,203 Days
• Field of Search: 370/328, 370/360, 370/469, 455/424, 455/404, 455/469
• US Class Current: 370/328
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders
• CPC Class Codes: G06Q 30/0633 Lists, e.g. purchase orders, compilation or processing
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 76/12 Setup of transport tunnels
• CPC Class Codes: H04W 8/02 Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
• CPC Class Codes: H04W 84/14 WLL [Wireless Local Loop]; RLL [Radio Local Loop]
• CPC Class Codes: H04W 88/00 Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 92/04 Interfaces between hierarchically different network devices

Abstract

A communication system having a wireless trunk for connecting multiple phone lines over wireless communication links to a cellular network comprises a central telephone switch, such as a private branch exchange or key system, connected through one or more trunk lines to a wireless access communication unit. The wireless access communication unit preferably comprises a separate subscriber interface for each trunk line from the central telephone switch. The wireless access communication unit collects data from each of the subscriber interfaces, formats the data into a format compatible with an over-the-air protocol, and transmits the information over one or more wireless channels to a cellular base station. The wireless access communication unit thereby connects calls received from the central telephone switch'"'"'s trunk lines over a wireless trunk to a network. A controller within the wireless access communication unit interfaces the subscriber interfaces with a radio transceiver, and assists in the conversion of data from a format suitable for wireless transmission. The controller also assists in distributing data received over the wireless trunk to the separate subscriber interfaces, and converting the data to a format suitable for communication with the central telephone switch. Calls may be selectively routed by the central telephone switch over landlines, instead, to the wireless access communication unit, thereby bypassing landlines.

Claims

1. A method of communication, comprising the steps of:

establishing a wireless connection between a wireless access communication unit and a base station subsystem of a cellular network, said wireless access communication unit connected to a plurality of non-wireless units;

performing connection management and mobility management functions between said wireless access communication unit and a mobile switching center using GSM connection management and GSM mobility management protocols end-to-end between said wireless access communication unit and said mobile switching center, said connection management and mobility management functions providing at least call set-up, maintenance and release functions for each of said non-wireless units;

transporting call data over said wireless connection between said wireless access communication unit and said base station subsystem using a non-GSM over-the-air physical layer protocol; and

transporting said call data between said base station subsystem and said mobile switching center using a GSM protocol.

2. The method of claim 1, wherein

said base station subsystem comprises a plurality of base stations connected to a base station controller,

said step of transporting call data over said wireless connection between said wireless access communication unit and said base station subsystem using a non-GSM over-the-air physical layer protocol comprises the step of transporting call data between said wireless access communication unit and a base station of said base station subsystem, and

said step of transporting said call data between said base station subsystem and a mobile switching center using a GSM protocol comprises the step of transporting said call data between said base station controller and said mobile switching center using said GSM protocol.

3. The method of claim 2, further comprising the step of establishing a plurality of bearer paths between said wireless access communication unit and said mobile switching center, each bearer path corresponding to one of said non-wireless units connected to said wireless access communication unit.

4. The method of claim 3, further comprising the step of establishing and maintaining a plurality of SCCP links between said base station controller and said mobile switching center, one SCCP link for each of said bearer paths.

5. The method of claim 1, wherein said step of transporting call data over said wireless connection between said wireless access communication unit and said base station subsystem using a non-GSM over-the-air physical layer protocol comprises the step of transporting said call data using an IS-661 format.

6. The method of claim 1, wherein said step of transporting call data over said wireless connection between said wireless access communication unit and said base station subsystem using a non-GSM over-the-air physical layer protocol comprises the steps of:

assigning, from among a plurality of time slots of a time frame, one or more duplex time slots to said wireless access communication unit, one of said duplex time slots being assigned for each non-wireless communication unit desiring to communicate over said wireless connection;

transmitting, over a first frequency band, user-to-base traffic messages from the wireless access communication unit to a base station of said base station subsystem during a user transmission segment in each of said duplex time slots; and

transmitting, over a second frequency band, base-to-user traffic messages from said base station to said wireless access communication unit during a base transmission segment in each of said duplex time slots.

7. The method of claim 6, wherein said user transmission segment and said base transmission segment of each duplex time slot are separated by one-half the duration of said time frame.

8. A method of communication, comprising the steps of:

establishing a wireless connection between a wireless access communication unit and a base station of a cellular network, said wireless access communication unit connected to a plurality of non-wireless units;

performing connection management and mobility management functions between said wireless access communication unit and a mobile switching center using GSM connection management and GSM mobility management protocols end-to-end between said wireless access communication unit and said mobile switching center, said connection management and mobility management functions providing at least call set-up, maintenance and release functions for each of said non-wireless units;

transporting call data over said wireless connection between said wireless access communication unit and said base station using a non-GSM over-the-air physical layer protocol;

transmitting call data received from said wireless access communication unit over a backhaul connection from said base station to a base station controller;

relaying said call data received from said wireless access communication unit from said base station controller to said mobile switching center using a GSM protocol;

transmitting from said mobile switching center to said base station controller call data intended for said wireless access communication unit using said GSM protocol; and

relaying said call data intended for said wireless access communication unit to said base station over said backhaul connection.

9. The method of claim 8, wherein said step of transporting call data over said wireless connection between said wireless access communication unit and said base station using a non-GSM over-the-air physical layer protocol comprises the step of transporting said call data using an IS-661 protocol.

10. The method of claim 8, wherein said step of transporting call data over said wireless connection between said wireless access communication unit and said base station using a non-GSM over-the-air physical layer protocol comprises the steps of:

assigning, from among a plurality of time slots of a time frame, one or more duplex time slots to said wireless access communication unit, one of said duplex time slots being assigned for each non-wireless communication unit desiring to communicate over said wireless connection;

transmitting, over a first frequency band, user-to-base traffic messages from the wireless access communication unit to said base station during a user transmission segment in each of said duplex time slots; and

transmitting, over a second frequency band, base-to-user traffic messages from said base station to said wireless access communication unit during a base transmission segment in each of said duplex time slots.

11. The method of claim 10, wherein said user transmission segment and said base transmission segment in each duplex time slot are separated by one-half the duration of said time frame.

12. The method of claim 8, wherein said step of transporting call data over said wireless connection between said wireless access communication unit and said base station using a non-GSM over-the-air physical layer protocol comprises the step of transmitting signaling messages between said wireless access communication unit and said base station.

13. The method of claim 8, wherein said step of transporting call data over said wireless connection between said wireless access communication unit and said base station using a non-GSM over-the-air physical layer protocol comprises the step of transmitting bearer traffic messages between said wireless access communication unit and said base station for each non-wireless unit communicating over said wireless connection.

14. A communication system, comprising:

a base station;

a wireless access communication unit connected to a plurality of non-wireless units, said wireless access communication unit providing a communication path between said base station and said non-wireless units, said communication path including a wireless connection over which said wireless access communication unit and base station communicate using a non-GSM over-the-air physical layer protocol;

a base station controller connected to said base station; and

a mobile switching center connected to said base station controller, said mobile switching center and said base station controller communicating using a GSM protocol, said mobile switching center and said wireless access communication unit performing connection management and mobility management functions using GSM connection management and GSM mobility management protocols end-to-end, said connection management and mobility management functions providing at least call set-up, maintenance and release functions for each of said non-wireless units.

15. The communication system of claim 14, wherein said non-GSM over-the-air physical layer protocol comprises an IS-661 over-the-air protocol.

16. The communication system of claim 14, wherein said base station comprises at least two backhaul transceivers.

17. The communication system of claim 16, wherein said backhaul transceivers comprise logical terminal endpoints, each backhaul transceiver supporting a first logical link for traffic signaling and a second logical link for operations, administration and management signaling.

18. The communication system of claim 17, wherein said base station multiplexes said first logical link and said second logical link of each of said backhaul transceivers onto a single time slot for communication to said base station controller.

19. The communication system of claim 17, wherein functional entities of said base station are addressable using service access point identifiers.

20. The communication system of claim 14, wherein said base station controller and said wireless access communication unit comprise endpoints for voice encoding and decoding.

21. The communication system of claim 14, wherein said base station controller and said wireless access communication unit comprise endpoints for encryption and decryption of bearer traffic.

22. The communication system of claim 14, wherein said base station controller and said wireless access communication unit comprise endpoints for forward error correction.

23. The communication system of claim 14, further comprising a transcoding unit, wherein said mobile switching center is connected to said base station controller through said transcoding unit.

24. The communication system of claim 14, wherein said base station controller and said mobile switching center communicate across a GSM A-interface.

25. The communication system of claim 14, wherein said wireless access communication unit is connected to said non-wireless units through a local area telephone switch.

26. The communication system of claim 25, wherein said local area telephone switch comprises either a private branch exchange (PBX) or key telephone system (KTS).

27. The communication system of claim 25, wherein said wireless access communication unit comprises

a plurality of subscriber ports connected to said local area telephone switch over a plurality of trunks;

a plurality of user interfaces connected to said subscriber ports, one user interface for each subscriber port;

a radio transceiver; and

a controller connected to said user interfaces and said radio transceiver, said controller managing the transfer of data between said user interfaces and said radio transceiver.

28. The communication system of claim 27, wherein said user interfaces are individually addressable.

29. The communication system of claim 27, wherein said base station controller and said mobile switching center maintain a plurality of SCCP links, one SCCP link for each user interface over which a call is connected from one of said non-wireless units.

30. The communication system of claim 27, wherein said wireless access communication unit sets up and maintains calls from said non-wireless units to said mobile switching center via said base station and said base station controller.

31. The communication system of claim 14, wherein said base station supports a multiple access communication protocol, said base station establishing wireless communication paths with mobile user stations upon demand.